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Compare Generators Side-by-Side

Select up to 4 generators to compare specs, power output, noise levels, runtime and more. Your compare URL is shareable.

  • Sportsman GEN4000iOF
  • Yamaha EF2800i
  • Model GEN4000iOF
    Model GEN4000iOF

    Sportsman 3,500W Gas Generator

    3500W
    Running
    65 dB
    Noise
    View details
  • Model EF2800i
    Model EF2800i

    Yamaha 2,500W Gas Generator

    2500W
    Running
    65 dB
    Noise
    View details
Quick charts
Each chart uses its own Y-axis scale (so numbers are comparable within a chart).
Running watts
W
Starting watts
W
Noise
dB
Runtime @50%
h
Running watts by fuel
Shows how output changes across gasoline/propane/natural gas (when available).
Generator Specifications Comparison
SpecificationSportsman GEN4000iOFYamaha EF2800i
General
Product type
Generator
Generator
Fuel
Gasoline
Gasoline
InverterYesYes
Parallel capableYesNo
RV readyYesNo
Running watts
Winner: Winner: 3500 W
2500 W
Starting watts
Winner: Winner: 3850 W
2800 W
Noise (lower limit)
Winner: Winner: 65 dB
Winner: Winner: 65 dB
Weight
93 lbs
Winner: Winner: 68 lbs
Run time @50% load
Winner: Winner: 10 h
Not available—
Run time @25% load
Not available—
14.7 h
Fuel tank
4.5 gal
2.6 gal
Fuel gaugeYesYes
Approx. dimensions (L × W × H)
23 x 17.5 x 20.3
19.2 x 15.6 x 16.7
Electrical
Voltage (AC)
120
120
Voltage (DC)
5
12
GFCI outletsNoYes
Covered outletsNoNo
Automatic Voltage RegulationYesYes
THD
5 %
2.5 %
Engine
Engine
223 cc OHV 4-stroke
Yamaha MZ175 OHV 4-stroke
Alternator
Not available—
Not available—
Starting system
Recoil
Recoil
Warranty
Warranty
1 years
3 years
Power by fuel
GasolineNot available—Not available—
Running watts
3500 W
2500 W
Starting watts
3850 W
2800 W
Running amps (120V)
Not available—
Not available—
Running amps (240V)
Not available—
Not available—
Peak amps (120V)
Not available—
Not available—
Peak amps (240V)
Not available—
Not available—
Run time @50% load
10 h
Not available—
Run time @25% load
Not available—
14.7 h
Other
Data center
Not available—
Not available—
Indicators
true
true
Compliance
EPA
EPA
Security
Not available—
Not available—
Spark arrestorYesYes
Neutral
Not available—
Not available—
UPC
27077805437
799530396645
Core / High-priority specs
Running Watts (Gasoline)
3500
2500
Starting Watts (Gasoline)
3850
2800
Runtime @ 50% Load (Gasoline)
10
Not available—
Runtime @ 25% Load (Gasoline)
Not available—
14.7
AC Outlet Types
1x Duplex 120V 20A (5-20R)1x 120V 30A (TT-30R)
1x Duplex 120V 20A (5-20R) GFCI1x 120V 30A (L5-30R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
223 cc OHV 4-stroke
OHV 4-stroke
Engine Displacement
223
171
Engine Oil Type
SAE 10W30
Not available—
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
Not available—
14.7
Runtime @ 50% Load (Gasoline)
10
Not available—
Safety & compliance
Overload Protection System
Low oil and overload protection
Not available—
Low Oil ProtectionYesYes
Included equipment
Included Accessories
Tool kit
Not available—
Additional specs
Summary
The Sportsman GEN4000iOF is a gasoline-powered inverter generator delivering 3,850 surge watts and 3,500 running watts, suitable for powering sensitive electronics with its clean sine wave output.
The Yamaha EF2800i is a lightweight and quiet inverter generator capable of powering a range of devices, from power tools to sensitive electronics, making it suitable for home backup, job sites, and on-the-go use.
  • Most Powerful
    Sportsman GEN4000iOF
    3500W running
  • Quietest
    Sportsman GEN4000iOF
    65 dB
  • Longest Runtime
    Sportsman GEN4000iOF
    10h at 50% load
Where to buy
Prices can change. We update these automatically.
Sportsman GEN4000iOF
Store links
No links yet.
Yamaha EF2800i
Store links
No links yet.
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